XMDS: don't add global default to SQL if not set. xibosignage/xibo#2378
XMDS: don't add global default to SQL if not set. xibosignage/xibo#2378

xibosignage/xibo-cms,dasgarner/xibo-cms,dasgarner/xibo-cms,dasgarner/xibo-cms,xibosignage/xibo-cms,xibosignage/xibo-cms,dasgarner/xibo-cms,dasgarner/xibo-cms,dasgarner/xibo-cms,xibosignage/xibo-cms,xibosignage/xibo-cms,xibosignage/xibo-cms